THE long-running saga over the future of a historic railway tunnel took a dramatic turn today as Bradford Council announced planning rules may have been breached by the Department for Transport (DfT).

A Council engineer has been sent to the tunnel - currently at the centre of a huge campaign to transform it as part of a multi-million pound cycle plan - to make an emergency assessment of its condition.

It follows last week's development when the DfT, which owns the site, began emergency measures to stabilise an air shaft in the face of its "increasingly deteriorating condition" caused by an influx of water.

The work has thrown the re-opening of the tunnel into doubt, with Highways England, which looks after the tunnel on behalf of the DfT, admitting the safety procedures will make it "more challenging" to bring it back into use.

Campaigners say the measures go too far and do not need to be implemented.

Now Council leader Susan Hinchcliffe has requested Secretary of State Grant Shapps to urgently intervene in what the Council believes are unauthorised actions.

In the letter, Councillor Hinchcliffe asks for an immediate halt to attempts to fill and seal a shaft at the Victorian tunnel and for an independent third party evaluation to assess its condition and use of emergency powers.

She has requested that Highways England withdraw a planning application to seal other shafts at the tunnel, and that representatives of the Department for Transport visit Bradford and the site to discuss funding options.

Bradford Council says the latest action follows efforts taken by the authority last week, including sending an urgent hand delivered letter to Highways England saying the correct planning process hadn’t been followed.

A second letter was sent demanding an immediate halt to works.

The current planning application from Highways England to fill and seal the tunnel has received more than 4,000 objections and is one of the most commented on applications Bradford Council has ever processed.

Councillor Hinchcliffe said: “Campaigners for the tunnel have been brilliant and we are all backing them.

“The actions of Highways England, which have happened without warning, have put the whole project in jeopardy.

“We need them to halt all the works and withdraw the planning application to seal the tunnel.”

A spokesperson for Highways England told the Telegraph & Argus last week: “This is not a decision taken lightly and the highest level of legal advice has been taken.

“The infilling of the shaft in this manner means that any reopening is going to be more challenging, however it could be reversed if an alternative owner came forward to reopen the tunnel in future.

“In the meantime our priority is completing the emergency work to ensure both the safety of those communities living close by and the workforce who need to maintain it.”

Highways England says the tunnel has received the highest risk ranking since September 2013. The application can be viewed by searching 19/02242/MAF at planning.bradford.gov.uk